we used to run the hotplug code in keventd_wq. But when hot removing the ACPI battery device, power_supply_unregister invokes flush_scheduled_work. This causes a deadlock. Introduce a new workqueue for hotplug in this patch. http://bugzilla.kernel.org/show_bug.cgi?id=13533 Tested-by: Paul Martin <pm@xxxxxxxxxx> Tested-by: Vojtech Gondzala <vojtech.gondzala@xxxxxxxxx> Signed-off-by: Zhang Rui <rui.zhang@xxxxxxxxx> --- drivers/acpi/osl.c | 23 ++++++++++++++--------- 1 files changed, 14 insertions(+), 9 deletions(-) diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c index d916bea..80488db 100644 --- a/drivers/acpi/osl.c +++ b/drivers/acpi/osl.c @@ -79,6 +79,11 @@ static acpi_osd_handler acpi_irq_handler; static void *acpi_irq_context; static struct workqueue_struct *kacpid_wq; static struct workqueue_struct *kacpi_notify_wq; +/* + * run the hotplug code in a seperate workqueue + * to avoid the deadlock issue + */ +static struct workqueue_struct *kacpi_hotplug_wq; struct acpi_res_list { resource_size_t start; @@ -192,8 +197,10 @@ acpi_status acpi_os_initialize1(void) { kacpid_wq = create_singlethread_workqueue("kacpid"); kacpi_notify_wq = create_singlethread_workqueue("kacpi_notify"); + kacpi_hotplug_wq = create_singlethread_workqueue("kacpi_hotplug"); BUG_ON(!kacpid_wq); BUG_ON(!kacpi_notify_wq); + BUG_ON(!kacpi_hotplug_wq); return AE_OK; } @@ -206,6 +213,7 @@ acpi_status acpi_os_terminate(void) destroy_workqueue(kacpid_wq); destroy_workqueue(kacpi_notify_wq); + destroy_workqueue(kacpi_hotplug_wq); return AE_OK; } @@ -716,6 +724,7 @@ static acpi_status __acpi_os_execute(acpi_execute_type type, acpi_status status = AE_OK; struct acpi_os_dpc *dpc; struct workqueue_struct *queue; + work_func_t func; int ret; ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Scheduling function [%p(%p)] for deferred execution.\n", @@ -740,15 +749,11 @@ static acpi_status __acpi_os_execute(acpi_execute_type type, dpc->function = function; dpc->context = context; - if (!hp) { - INIT_WORK(&dpc->work, acpi_os_execute_deferred); - queue = (type == OSL_NOTIFY_HANDLER) ? - kacpi_notify_wq : kacpid_wq; - ret = queue_work(queue, &dpc->work); - } else { - INIT_WORK(&dpc->work, acpi_os_execute_hp_deferred); - ret = schedule_work(&dpc->work); - } + queue = hp ? kacpi_hotplug_wq : + (type == OSL_NOTIFY_HANDLER ? kacpi_notify_wq : kacpid_wq); + func = hp ? acpi_os_execute_hp_deferred : acpi_os_execute_deferred; + INIT_WORK(&dpc->work, func); + ret = queue_work(queue, &dpc->work); if (!ret) { printk(KERN_ERR PREFIX -- 1.5.4.4 -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
